ADR-002: Axum Web Framework

Status

Accepted

Context

We need a web framework for:

• WebSocket handling
• REST API endpoints
• Middleware support (auth, logging, CORS)
• Integration with async Rust ecosystem

Options considered:

• Actix-web: Mature, but complex macro system
• Warp: Functional, steeper learning curve
• Axum: Tower-based, type-safe, simpler mental model

Decision

Use Axum as the web framework.

Consequences

Positive

• Built on Tower, excellent middleware ecosystem
• Type-safe extractors reduce runtime errors
• Simple, predictable API
• First-class WebSocket support
• Excellent integration with Tokio

Negative

• Newer than Actix, smaller community
• Some patterns still evolving

Mitigation

• Follow official examples
• Contribute upstream if gaps found